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The technological quality of the protein fraction of wheat white flour (WW) was determined by the lactic acid Solvent Retention Capacity and by the Gluten Performance Index (LA-SRC and GPI; AACC method 56-11.01). Parallelly, Perten's standard Gluten Index test (GI; AACC method 38-12.02) was performed with that wheat control. Consequently, the same methods were applied to 9 bi-composite blends mixed at ratios of 90 : 10, 80 : 20, 70 : 30, 60 : 40, 50 : 50, …, and 10 : 90 as WW replacement with one of the rye bread flours (RB), and the RB control itself. Unlike successful measurements in the case of the LA-SRC and GPI, washing gluten from the first 90 WW : 10 RB blend led to the clogging of the Glutomatic sieve, likely due to the interaction of wheat gluten with rye arabinoxylans. The discrepancy induced the development of a modification of the standard GI procedure; clogging was avoided by precipitating flour and centrifuging the swollen solid from suspension, similarly like in the SRC method. The settled residue transported to a standard sieve cassette was secondly centrifuged in the original apparatus Perten CF2015. The weighing of the overflow and underflow of the sieve and the calculation of the results were performed according to the original GI method. For the WW control, the standard GI value was 90% and the modified Gluten Index value (GImodif) was 82%. As expected for WW-RB counterparts, the higher the portion of rye in the bi-composite blend, the lower the value of the GImodif . For the 50 WW : 50 RB blend and the RB itself, the GImodif values were 47% and 18% (the GPI values 0.66, 0.45, and 0.39, respectively). On the contrary, the LA-SRC demonstrated a convex course (118, 104, and 123%, respectively). In the plane of the principal components (PC), namely PC1 and PC2, the variables related to gluten quality formed 4 groups as a function of the stepwise change in the mixing ratio of WW and RB: i) flour protein content, GPI, and GImodif ; ii) LA-SRC; iii) dietary fibre content and ash content; iv) water, sucrose, and sodium carbohydrate SRCs. However, the modified test procedure should be revised in wheat varieties characterised by a wider spectrum of protein quality, mixed with different types of rye flour (especially wholegrain one).

A traditional Czech bakery white bread product is commonly made with directly mixed dough with the addition of yeast. In order to be able to reduce the salt content of the final product without compromising its acceptability to consumers, the dough was prepared with the addition of pre-ferments and wheat sourdoughs. The aim was to deepen the flavour background of the product and thus have a positive effect on its sensory properties. Wheat sourdoughs were prepared and tested using starter cultures and matured under different conditions. The resulting products were tested both sensorially and by means of precise physical methods.

Rye is a later cereal compared to wheat and barley. The main use of rye in human nutrition consists in the processing of grain to flour (dark and wholemeal) and in the baking industries in sourdough and bread making. During the last fifty years, there has been a decline in the consumption of rye in the Czech Republic. Rye is a nutritionally interesting cereal due to its high fibre content. The part of the review presents the development of consumption of rye and rye products, nutritional significance of rye products, changes in the properties and content of rye grain components during processing with a focus on the evaluation of the effect of milling on components and microstructure of rye flour.

To study the effect of quinoa and canahua wholemeals on wheat flour quality, addition dosages of 10 and 20% wt. were tested. Both non-traditional materials lowered protein baking quality (Zeleny sedimentation), and present dietary fibre increased the Falling number. The fermentograph and maturograph tests showed differences in the optimal fermentation and proofing times, as well as in dough volumes during both tests (which were somewhat higher for the wheat-quinoa flour composites). Besides this, dough volumes in the third stage of fermentation simulated on the oven-rise apparatus decided about baking trial results; in this regard, wheat-canahua flour composites reached statistically better results. All obtained data together with sensory scores pointed to the maximal tolerable quinoa or canahua dosage up to 15% wt.

Linseed fibre represents a rich natural source of dietary fibre. Here, we report that the addition of linseed fibre at levels of 2.5 and 5.0% changes the viscosity of wheat flour as well as the rheological properties of non-fermented and fermented dough. The differences recorded between fibre from golden and brown flax seeds (GF and BF, respectively) were not significant; BF caused a stronger increase in non-fermented dough elasticity. The addition of both variants reduced fermentation times and partially decreased dough volumes during the three phases of the fermentation process. The results of the baking test corresponded with the altered rheological parameters of dough. Based on principal component and cluster analyses, representative features for each rheological test were identified: amylograph maximum (amylograph test), the pasting temperature (RVA test), dough softening degree (farinograph test), extensigraph ratio (extensigraph test) were selected as the representative features. For the evaluation of fermented dough behaviour, wheat flour-linseed fibre composites could be differentiated according to fermentation time (fermentograph test) and dough volume (OTG test). Statistics also confirmed the appropriateness of the crumb firmness parameter for a detailed specification of bread quality.

Basic wheat-barley flour premixes were blended at ratios 70 : 30 and 50 : 50 (w/w), and white or dark types of wholemeal chia and teff replaced 5 or 10% of these bases. All non-traditional plant materials increased farinograph water absorption up to 10% in total, and with likely dilution of the dough gluten network, their addition increased the degree of dough softening up to twice. Physicomechanical properties of non-fermented dough were changing stepwise, mainly in terms of rising dough elasticity. Higher elasticity of wheat-barley dough was reflected in better both specific volume and spread ratio of cut-out cookies. Further recipe modification by wholemeal chia and teff flours enhanced these positive changes; cookie volumes based on the wheat-barley premix 50 : 50 were about 22% higher than their counterparts from the premix 70 : 30. For both attributes of cookie quality, somewhat higher values were observed for dark variants of wholemeal chia and teff. Moreover, the spread ratio of cookies containing teff types reached higher values compared to chia ones. Characteristic barley flour flavour could be less acceptable for common consumers; both wholemeal chia and teff flours were able to mask that by-taste.

Correspondingly to addition levels, barley flour supplement changed the wheat SRC profile and rheological behaviour as expected, and positively influenced its cookie making potential. Dehulled or covered hemp seeds wholemeal flour types and commercial fine hemp flour differed in their impact on the wheat-barley SRC scores. Rheological behaviour of flour tri-composites was changed in terms of a reduction of dough tolerance to overmixing, and that fact was positively reflected in baking test results. Compared to cookies with 30% of barley flour in recipe, volumes increased significantly as a result of the fine hemp flour addition only (from 150.3 ml/100 g to 173.4 ml/100 g, i.e. +15%). Their spread ratio was worsened to the same extent, it diminished from 4.54 to 3.86. For sample counterparts containing 50% of barley flour, determined values were 138.3 vs. 153.2 ml/100 g (+11%) and 4.75 vs. 5.16, respectively. Within the cluster analysis, a tree-plot verified the similarity of both wheat flour standards as well as of both wheat-barley premixes. Further grouping was linked according to the barley flour ratio, and secondarily according to the hemp flour type tested.

Barley is known as health-benefit raw material, mainly due to beta-glucan. To explore the nutritional benefit of barley and hemp plants, wheat-barley flour premixes were prepared (70 : 30 and 50 :0 50 w/w, respectively). Hemp flour of wholemeal and fine type was added to each cereal base on levels of 5 and 10%. Barley flour diminished both protein content and its quality, but it played a positive role in an increase in amylase activity. Hemp addition levelled the protein content back (at least to the value comparable to wheat flour), but its quality was worsened further correspondingly to a hemp portion. Enzymatic activity of the composite was modified weakly by the non-traditional material. Determining the SRC profiles of wheat-barley and wheat-barley-hemp blends, changes mentioned above were sufficiently verified.

We examine the nutritional effect of selected non-traditional grain samples added into wheat flour. In a form of flour, amaranth, quinoa, lupine, 5 hemp types, 2 teff types and 2 chia types were used for wheat flour substitution on a low and high level. Samples with amaranth and lupine flour showed the best improvement in terms of protein content (in the range between 21.1 and 26.0%). The highest total dietary fibre was found in lupine composites (7.1 and 9.8%). Hemp samples contained a significant amount of minerals in comparison with the control wheat sample (from 1.16% to 1.98%). According to the above-mentioned differences, flour composites containing single tested grains were distinguished by principal component analysis. All examined plant materials could be recommended for wheat flour fortification in terms of nutritional improvement. The addition of non-traditional flours partially changed both the volume and shape of laboratory prepared bread correspondingly to the type and added amount.

The baking quality in the sets of both commercial and variety wheat samples (80 and 18 items) and wheat composite flour (standard and 25 blends) was evaluated in terms of the Solvent retention capacity method (AACC 56-11). Composites were prepared from a commercial fine wheat flour and commercial bio-wholemeal flour prepared by milling of common wheat, rye, oat, barleys and corn at substitution levels of 10, 20, 30, 40, and 50%. The commercial wheat quality testing ANOVA revealed the major effect of the sample tested form; the data measured for grain and flour proved to be correlated. Besides, the harvest year affected the baking quality to a greater degree than the growing locality. Within the variety wheat set, the harvest year factor dominated over that of the wheat cultivar one with the exception of the sodium carbonate retention capacity. In the case of the wheat flour substitution by bio-cereal flour types, the added amount of the alternative flour supported only the quantitative change caused by the incorporated cereal in all four retention capacities.

The analysis of the wheat hardness relation to other quality features was done with a set of 281 variety and commercial wheat samples, planted during the years of 2003-2006 in Central Bohemia and south Moravia areas. Technological quality was evaluated for grain, milling process, and flour analytics with the standard laboratory methods. The grain hardness was measured using NIR spectrophotometer Inframatic 8600. Tukey's test (ANOVA) of the grain hardness was performed for comparison between the means of wheat variety, wheat origin, crop year, growing locality, and farming intensity. As expected, the grain hardness of wheat varieties belonging to different quality classes was independent of either their classification or winter/spring type. Between all four locality means, the grain hardness among 281 samples differed insignificantly, while in the crops of 2004 and 2006 a provable increase of the kernel compactness was observed. The correlation analysis confirmed a role of the grain hardness in the milling quality assessment because of the proved correlation with 11 grain and milling quality features from the 12 tested. The strongest relation was calculated with the grain ash content, semolina yield, and flour protein content (-0.55, 0.52, 0.42, respectively).

The colour of the laboratory prepared pasta was evaluated with respect to wheat flour types (M1 bright, M2 semi-bright, and M3 semolina), egg-ratio (0, 1, 2), and non-traditional cereals (archaic wheat species, tritordeum, spring barley, millet, lupin, buckwheat, and soya) supplements. The flour colour measurement confirmed its dependence on the wheat species milled - M3 obtained from durum wheat had a lower whiteness L* (89.6) and a higher yellowness b* (22.2) than the flour from common wheat (e.g. 93.6 and 8.1 for M1, respectively). As presumed, with the rising egg-ratio pasta yellowness increased - for M1-pasta, the calculated colour differences ∆E in pairs one-egg/eggless and two-egg/eggless were 1.1 and 4.7, respectively, while for M2- and M3-pasta ∆E values were only 0.8 and 1.5, respectively. The colour impacts of non-traditional cereals as 10% supplements differed between archaic wheat species, tritordeum, barley, and alternative cereals (millet, lupin, roasted buckwheat). In comparison to the standard, the greatest positive colour gain was brought by the lupin fortification (130% yellowness increase), while the worst appesred roasted buckwheat (10% decrease of whiteness, 210% increase of redness). At 20% non-traditional cereals supplements compared for M2- and M3-pasta, the highest positive increase of the pasta colour sensory perception was caused by corn and lupin additions in both pasta samples. The increase was slightly higher with M1-pasta (175%) than with M3-pasta (170%). In the mean of both pasta samples, yellowness L* increased from the standard pasta value 13.6 to 24.0 as measured for corn and lupin fortified pasta.

The effects of wheat cultivar and harvest year on the wheat technological quality were studied by univariate and multivariate statistical methods. Two wheat varieties sown in the harvest years 2003-2005 were used, the first one of European (cultivar Bezostaja, RUS), the second one of American origin (cultivar Jagger, USA). The evaluated parameter values indicated otherness of technological quality of the varieties studied, mostly in the milling effectivity and in proteins contents and quality. Principal component analysis (PCA) results suggested these differences, but their verifiability based on ANOVA testing was not proved. The harvest year mostly affected also the milling quality and alveograph parameters. The baking test results were not affected by either of both effects studied. The crop of 2003 had higher proximity to the crop of 2004 than to that of 2005. Multivariate analysis (cluster analysis; CA), was used to evaluate the interaction between the wheat cultivar and harvest year effects. In comparison of these effects rate, the technological quality of American cultivar Jagger was strongly influenced by the cultivar (with exception of Falling Number and gases volume). In contrast, the quality of the European wheat cultivar Bezostaja depended significantly on the harvest year.

Bakery characteristics of wheat dough and the final product and their predictability by NIR technique was investigated using 231 variety and commercial wheat samples (crop years 2003-2005). The behaviour of doughs was assessed with Brabender maturograph and OTG (Germany), the final product quality was evaluated by the baking test and image analysis. NIR spectra of flours were acquired on a NIRSystem 6500 spectrometer. Calibration equations for the selected rheological characteristics were computed by WINISI II using mPLS regression. The quality of prediction was evaluated by means of coefficients of correlation between measured and predicted values from cross and independent validation. A statistically significant dependence (with probability higher than 99%) was found with all rheological characteristics. The standard errors of cross-validation were achieved as follows: dough elasticity 16 BU, bread volume (11 min) 58 BU, specific loaf volume 34 cm3/100 g, bread cut area 2.6 cm2, penetration 4.1 mm, average cell area 0.4 mm2 and cells per cm2 7.4.

For the CIE Lab colour profile determination of laboratory prepared pasta, two sample granulations and two spectral methods were tested. Pasta was manufactured progressively from semolina, common wheat, and corn flour. Sufficient colour spectra ranges were ensured by means of fortification with 9 non-traditional cereals in the first case, 8 natural colorants in the second one, and with 12 gluten-free pasta recipes in the last case. Both factors (i.e. granulation and spectral method) were proved as statistically significant by the cluster, variance and principal component analyses. In the comparison of the effects on the pasta composition and the spectral method, the latter demonstrated a stronger impact on the pasta colour profile measured.